IDMS SP #3 Performance Concerns

We are a Z/OS 1.4 shop running IDMS-DC with a mix of ADS/O, DC-COBOL,
CICS COBOL as well as COBOL batch applications.

We recently implemented IDM SR16 SP #3 on one our production systems and
have experienced intermittent online performance issues. Displays of
storage and program pool usage look fine. Buffering is unchanged.
Storage protect is on as it has always been in order to protect the
system from misbehaving COBOL apps which our I/S folks seem unwilling or
unable to fix. Batch activity is present but at normal levels.

Performance on several other systems running this software is fine.

The only thing out of the ordinary I can point to is the fact that
journal reports show a few problem applications doing some extreme
levels of I/O activity when problems occur. Unfortunately, because
of local political issues, I can't set system limits at reasonable
levels to prevent this. I should note we have occasionally seen these
types of problems on this system in the past when these apps do this
type of extreme processing.

Nevertheless, I have been told to see if the R16 SP #3 upgrade is
responsible for the observed problems.

I therefore ask for any input on known performance issues with R16 SP
3#.

I guess if the performance problems occur during the times that the extreme
levels of I/O then all that you can do is attempt to cover it in the buffers
if they must go through.

Other random thoughts - Look through the current list of published PTFs (and
unpublished) on the IDMS 16 FTP site. Collect and review PMIM and shutdown
stats. Check all your options in terms of tuning, Make sure you covered
all the steps in the install - $README member + cover letter + intall guide.
You didn't mention which release you came from to get to 16. You may need
to check you covered the intervening release level notes. Look at LE
options - CEEUOPT module - for your COBOL. Storge Protect at the SYSTEM
level or the program level - look for any gotchas from the install in this
area.

CPU areas that can cause problems - did you turn on Multitasking? (+10ish%)
Did you turn on SYSTRACE? (+2 to +10%)

We are a Z/OS 1.4 shop running IDMS-DC with a mix of ADS/O, DC-COBOL,
CICS COBOL as well as COBOL batch applications.

We recently implemented IDM SR16 SP #3 on one our production systems and
have experienced intermittent online performance issues. Displays of
storage and program pool usage look fine. Buffering is unchanged.
Storage protect is on as it has always been in order to protect the
system from misbehaving COBOL apps which our I/S folks seem unwilling or
unable to fix. Batch activity is present but at normal levels.

Performance on several other systems running this software is fine.

The only thing out of the ordinary I can point to is the fact that
journal reports show a few problem applications doing some extreme
levels of I/O activity when problems occur. Unfortunately, because
of local political issues, I can't set system limits at reasonable
levels to prevent this. I should note we have occasionally seen these
types of problems on this system in the past when these apps do this
type of extreme processing.

Nevertheless, I have been told to see if the R16 SP #3 upgrade is
responsible for the observed problems.

I therefore ask for any input on known performance issues with R16 SP
3#.